[Temporomandibular joint disorder after dental treatment]. / TMD-klachten na een tandheelkundige behandeling.

A 56-year-old woman presented with persistent unilateral gnathological complaints after replacing an amalgam restoration. The patient reported tension and pain in the right side of her jaw, along with crackling sounds in the temporomandibular joint. Physical examination revealed tenderness in the right masseter muscle and temporomandibular joint, as well as anterior disc replacement with reduction on both sides. The initial treatment focused on providing rest to the temporomandibular joint, the Yoda exercise, and later, wet-needling. Despite initially limited improvement, the symptoms persisted. This case underscores the complexity and various treatment options for temporomandibular joint issues following dental procedures.

Awareness of possible complications associated with direct composite restorations: A multinational survey among dentists from 13 countries with meta-analysis.

OBJECTIVES: Resin-based composites (RBCs) evolved into favoured materials for teeth restorations, marking a significant change in dental practice. Despite many advantages, RBCs exhibit various limitations in their physical and chemical properties. Therefore, we assessed the dentists' awareness of possible complications after direct composite restorations and their opinions about this material. METHODS: The online questionnaire was created in English in May 2023. A 16-item survey was dedicated to general dentists and specialists. The first section included four questions related to demographic characteristics. The second section comprised twelve questions and focused on awareness of potential side effects of composite restorations, the most crucial advantages and disadvantages of composite resins, and the frequency of experienced clinical complications after the application of composite materials. RESULTS: A total of 1830 dentists from 13 countries took part in the survey. Dentists most often declared awareness of low adhesion to the dentine (77.5 %) and, most rarely, solubility in oral fluids (42.6 %). Aesthetics was identified as the main advantage of composite fillings (79 %), followed by the possibility of repair (59 %) and adhesion to enamel (57 %). Polymerisation shrinkage was a major disadvantage for most countries (70 % overall). Analysing the declared potential clinical complications for all countries, statistically significant findings were obtained for marginal discolouration (OR=2.982, 95 % CI: 1.321-6.730, p-value=0.009) and borderline significance for secondary caries (OR=1.814, 95 % CI: 0.964-3.415, p-value=0.065). CONCLUSIONS: Dentists value aesthetics and repairability but are aware of shrinkage and experience discolouration. The issue of toxicity and solubility seems to be the least known to dentists. CLINICAL SIGNIFICANCE: Dentists should use RBCs with critical caution due to possible side effects. Despite the undoubted aesthetics of direct composite restorations, it is necessary to remember potential clinical complications such as marginal discolouration or secondary caries.

Predictors of apical periodontitis in root canal treated teeth from an adult Nepalese subpopulation: a cross-sectional study.

BACKGROUND: Endodontic literature search revealed that no study has been conducted to evaluate the prevalence of apical periodontitis (AP) in root canal treated teeth from an adult Nepalese population of Madhesh Province. Consequently, little is known about the extent and risk factors associated with it. This study aimed to determine AP prevalence in root canal treated teeth from an adult Nepalese subpopulation and to analyze the related risk factors including age, sex, tooth type, type of coronal restoration and quality of root canal treatment and coronal restoration as predictors of AP. METHODS: Digital panoramic radiographs were evaluated. Periapical status of 300 root canal-treated teeth was scored by using the periapical index. The quality of root canal treatment and coronal restorations were categorized as adequate or inadequate through radiographic and clinical evaluation. The data were analyzed using univariate and multivariate logistic regression models. RESULTS: Prevalence of AP in the present study was 31.7%. In 45.7% of the treated teeth, quality of root canal treatment was adequate whereas 46% of the cases had adequate coronal restorations. Multivariate logistic regression analysis revealed statistically significant associations and remarkably increased risk for AP in teeth with inadequate root canal treatment (odds ratio [OR] = 7.92; 95% CI: 3.96-15.82; p < 0.001) whereas lower risk for AP was found in females (OR = 0.51; 95% CI: 0.28-0.90; p = 0.021) and in teeth restored with crown (OR = 0.22; 95% CI: 0.09-0.51; p < 0.001) and filling (OR = 0.18; 95% CI: 0.08-0.42; p < 0.001). Quality of coronal restoration, tooth type and age of the patient were not found to be the predictors of AP. CONCLUSIONS: Within the limits of this study, a high prevalence of AP and poor overall quality of root canal treatment and coronal restoration was found in the subpopulation studied. Quality of root canal treatment, type of coronal restoration and sex of the patient are significant predictors of possible AP development in root canal treated teeth. Substantial efforts are needed to improve the endodontic treatment standards.

Comparative Assessment of Marginal Micro Leakage of Different Esthetic Restorative Materials Used on Primary Teeth: An In-vitro Study.

AIM: The aim of the current investigation was to evaluate the marginal microleakage of various esthetic restorative materials applied to primary teeth. MATERIALS AND METHODS: A total of 75 noncarious primary molars that were removed for orthodontic intervention and teeth nearing exfoliation were chosen. One millimeter (mm) above the cementoenamel junction, on the buccal surface of the teeth, Class V cavities were prepared. William's graded periodontal probe was used to standardize cavity preparation on all teeth. 3 mm was the cavity's length, 2 mm in width, and 2 mm in depth. The teeth were then divided into three groups (25 samples in each group) according to the type of esthetic restorative material used. Group I: Resin-modified glass ionomer cement, Group II: Ormocer, Group III: Giomer. The samples underwent 500 cycles of thermocycling, with an immersion time of 60 seconds and a well time of 15 seconds, between 5 and 55°C. The samples were submerged in methylene blue dye for 24 hours at room temperature and dried. The samples were then divided into sections and examined with a stereomicroscope. Data was recorded and statistically analyzed. RESULTS: The least marginal microleakage was found in the ormocer group (1.22 ± 0.01) followed by resin-modified glass ionomer cement group (1.31 ± 0.07) and the giomer group (1.78 ± 0.03). There was a highly statistically significant difference found between resin-modified glass ionomer cement group and the ormocer group, resin-modified glass ionomer cement group and giomer group. And no significant difference was found between the ormocer group and the giomer group. CONCLUSION: The present study concluded that there was some amount of microleakage in primary teeth in all restorative materials examined in this in-vitro investigation. However, the marginal sealing ability of ormocer was found highest compared to resin-modified glass ionomer cement and Giomer materials. CLINICAL SIGNIFICANCE: The primary reason dental restorations fail, particularly in Class V cavities, is microleakage since the margins of these restorations are typically found in the dentin or cementum. Assessing microleakage is a crucial step in determining the marginal integrity of restorative materials. Developing methods and resources that reduce the adverse effects caused by the restorative marginal seal failing would benefit from this. How to cite this article: Al Ghwainem A, Alqarni AS. Comparative Assessment of Marginal Micro Leakage of Different Esthetic Restorative Materials Used on Primary Teeth: An In-vitro Study. J Contemp Dent Pract 2024;25(1):58-61.

Adverse reactions to dental biomaterials: Experiences from a specialty clinic.

OBJECTIVES: The Dental Biomaterials Adverse Reaction Unit was initiated by the Norwegian health authorities in 1992 as a response to the public concern regarding the safety of dental amalgam and other dental materials. In this paper, experiences from the Unit are briefly summarized. METHODS: The Norwegian health authorities' strategy included four main topics: (i) development of a manufacturer-independent system for monitoring adverse reactions related to dental materials, (ii) funding of a specialty unit for clinical examinations of referred patients, (iii) development of official guidelines for examination and treatment of patients with health complaints attributed to dental materials, and (iv) funding of an experimental treatment project for patients with health complaints attributed to dental amalgam. RESULTS: From the start, more than 2700 adverse reaction reports were received. In the initial years, amalgam was the most frequent material mentioned in the reports. Reports about polymer-based composite materials have not increased after the prohibition of amalgam in Norway. Clinical examination of referred patients is complex and time consuming, and it is important to consider differential diagnoses. There are methodological challenges associated with the design of experimental treatments used on patients with adverse reactions attributed to dental materials. However, the results from the treatment project indicate lower symptom load after replacement of amalgam with other dental restorative materials. SIGNIFICANCE: Producer independent adverse reaction reporting can provide valuable information about the safety of these materials and could serve as a complement to the mandatory reporting system described in the European medical device regulations (MDR).

The potential of conventional and bulk-fill bioactive composites to inhibit the development of caries lesions around restorations.

PURPOSE: To determine caries inhibition potential of conventional and bulk-fill bioactive composites around restorations. METHODS: Enamel and dentin blocks were prepared using a diamond saw under water irrigation, finished (SiC, 600- and 800-grit) and polished (SiC 1,200, final polish= 0.2 µm). Blocks were then selected through enamel surface microhardness, and enamel and dentin standard cavities were restored (n=10/group) with conventional bioactive composite (Beautifil II, BTF), bulk-fill bioactive composite (Activa BioACTIVE, ACT), glass-ionomer cement (Ionofil Plus, ION), conventional composite (GrandioSO, GSO), and bulk-fill composite (Admira Fusion X-TRA, ADM). Afterwards, the blocks were subjected to pH cycling: 4 hours in demineralization and 20 hours in remineralization solutions for 7 days, before being cut in the middle. One half was used to calculate the carious lesion area (ΔS) using values obtained by cross-sectional microhardness (CSMH) testing. The other half was submitted to polarized light microscopy (PLM) and scanning electron microscopy (SEM). The % of internal gap formation (GAP) of restorations' replicas were analyzed under SEM. Data were analyzed by ANOVA and Tukey test (α= 5%). RESULTS: In terms of CSMH, ION group exhibited the lowest ΔS values, with no significant difference to ADM. The composites BTF and ACT were similar to each other (P< 0.05) and to their negative controls (GSO and ADM), respectively. ION showed lower caries formation under PLM, whereas the GSO group presented a greater demineralized area. ION presented the highest % of internal GAP formation. Bioactive composites (BTF and ACT) were similar to their corresponding conventional ones (GSO and ADM) in terms of GAP formation. CLINICAL SIGNIFICANCE: The glass-ionomer cement was more effective in inhibiting the formation of caries lesions around restorations. Because of the glass-ionomer cement's limited application in high load-bearing areas, the conventional bioactive composite would be a promising clinical choice.

Chapter 9.4: Operative Treatment and Monitoring of Coronal Caries in Daily Practice.

After the caries lesion reaches a certain extent of tooth structure loss, a restoration is often needed to repair the defect. Operative interventions in cariology aim to aid biofilm removal and lesion arrest by cavity sealing, avoid pulpal damage, and restore form, function, and esthetics. There are no clear evidence-based parameters to determine the most appropriate treatment option for each clinical situation. Despite of this, direct composite resins have been the preferable restorative treatment. Scientific literature shows that composites and adhesive strategies play a minor role in treatment success. Patient-related risk factors (mainly those associated with lifestyle and health choices), in addition to the dentist's decision-making process, play a significant role in longevity of the restorations, which tend to fail for the same reasons that lead to the need for restoration (dental caries, tooth/restoration fracture, and esthetics). Therefore, monitoring old restorations in clinical service, even if those present clear signs of degradation, is possible and reasonable within the concept of minimal intervention in dentistry. Unnecessary reinterventions are harmful and costly to health systems, and the clinician's efforts must be directed to eliminating or reducing the etiological factors that can cause the restoration to fail. Thus, patient risk factors assessment is a crucial point in monitoring restorations. Clinician should - whenever possible - postpone operative reinterventions, monitoring the etiological factors that may compromise the restoration's longevity. Also, when operative reintervention is necessary, refurbishment, polishing, and repair should be prioritized over replacement.

The Pulpal Response to Crown Preparation and Cementation.

INTRODUCTION: This study aimed to evaluate the risk factors and occurrence of pulpal disease in patients who received either full-coverage (crowns) or large noncrown restorations (fillings, inlays, or onlays involving ≥3 surfaces). METHODS: A retrospective chart review identified 2177 cases of large restorations placed on vital teeth. Based on the restoration type, patients were stratified into various groups for statistical analysis. After restoration placement, those who required endodontic intervention or extraction were classified as having pulpal disease. RESULTS: Over the course of the study, 8.77% (n = 191) of patients developed pulpal disease. Pulpal disease was slightly more common in the large noncrown group than the full-coverage group (9.05% vs 7.54%, respectively). For patients who received large fillings, there was not a statistically significant difference based on operative material (amalgam vs composite: odds ratio = 1.32 [95% confidence interval, 0.94-1.85], P > .05) or the number of surfaces involved (3 vs 4: odds ratio = 0.78 [95% confidence interval, 0.54-1.12], P > .05). The association between the restoration type and the pulpal disease treatment performed was statistically significant (P < .001). The full-coverage group more frequently underwent endodontic treatment than extraction (5.78% vs 3.37%, respectively). Only 1.76% (n = 7) of teeth in the full-coverage group were extracted compared with 5.68% (n = 101) in the large noncrown group. CONCLUSIONS: It appears that ∼9% of patients who receive large restorations will go on to develop pulpal disease. The risk of pulpal disease tended to be highest in older patients who receive large (4 surface) amalgam restorations. However, teeth with full-coverage restorations were less likely to be extracted.

Impact of dental restorations and removable prostheses on potentially malignant oral mucosal disorders in the general population.

STATEMENT OF PROBLEM: Dental restorations and removable dental prostheses have been considered as risk factors for potentially malignant disorders of the oral mucosa. It remains unclear whether amalgam, composite resins, and prosthesis materials can induce potentially malignant disorders. PURPOSE: The purpose of this clinical study was to determine the relationship between the presence of amalgam and composite resin restorations, crowns and fixed partial dentures, and removable prostheses in potentially malignant disorders. MATERIAL AND METHODS: The data of 6041 participants in the population-based Studies of Health in Pomerania (SHIP) were accessed. Potentially malignant disorders had been clinically diagnosed by calibrated dentists and documented with photographs. Dental treatment was subdivided into restored and replaced teeth. Dental restorations were subclassified as buccal composite resin or amalgam restorations. Prosthetic treatment was subclassified into removable partial or complete prostheses and definitive restorations with crowns and fixed partial dentures. RESULTS: In the maxilla, participants with removable prostheses had a higher incidence of potentially malignant disorders than participants not undergoing treatment with removable prostheses (OR 2.12; 95% CI: 1.08-4.18), but not in the mandible (OR 1.30; 95% CI: 0.67-2.53). The surfaces with composite resin restorations were associated with a slightly higher risk of mucosal lesions than those without the restorations (OR 1.04; 95% CI: 1.01-1.07). No significant association was found between amalgam restorations and mucosal lesions. CONCLUSIONS: Participants with removable prostheses have a higher risk of potentially malignant disorders. Composite resin restorations are associated with a higher risk of mucosal lesions, whereas no significant association was found between amalgam restorations and mucosal lesions.

Efficacy of adhesive strategies for restorative dentistry: A systematic review and network meta-analysis of double-blind randomized controlled trials over 12 months of follow-up.

PURPOSE: The efficacy of etch-and-rinse, selective enamel-etching, and self-etching protocols for universal adhesives in follow-ups of over 12 months was compared in a network meta-analysis. STUDY SELECTION: Randomized controlled trials (RCTs) published from 1998 to 2022 that compared marginal staining, marginal adaptation, retention and fractures, post-operative sensitivity, or recurrence of caries that took place over 12-months post-restoration were selected. A network meta-analysis determined the performance of each adhesive protocol. RESULTS: After screening 981 articles, 16 RCTs were subjected to data extraction. Of which, 674 patients with 2816 restorations, were included in the network meta-analysis. The pooled risk of marginal discoloration following self-etching was significantly higher than that following etch-and-rinse at over 12, 24, and 36 months, which was time-dependent. The pooled risks of unfavorable marginal adaptation and unfavorable retention and fractures following self-etching were also significantly higher than that following etch-and-rinse, with the rates of unfavorable retention and fractures in non-carious cervical lesions increasing in a time-dependent manner. The pooled risks of marginal discoloration, unfavorable marginal adaptation, retention and fractures were similar between etch-and-rinse and selective enamel-etching protocols. Post-operative hypersensitivity and recurrence of caries were not significantly different among etch-and-rinse, selective enamel-etching, and self-etching protocols. CONCLUSIONS: In follow-ups over 12 months, esthetic and functional outcomes of restorations completed with an etch-and-rinse adhesive protocol were superior to the ones achieved with a self-etching strategy without selective enamel-etching. Selective enamel etching is recommended for self-etching systems. Biological responses were similar for all three adhesive strategies.

Onset of oral lichen planus following dental treatments: A nested case-control study.

INTRODUCTION: The exposure to amalgam restorations has been reported to bring about altered immunity followed by inflammation and infection. AIMS: This study aimed at identifying whether patients who received restorative or endodontic treatments, or tooth extraction, would have altered odds of developing oral lichen planus (OLP). MATERIAL AND METHODS: In this population-based nested case-control study, 421 cases of OLP and 1,684 controls were included after propensity score matching. Logistic regression was used to estimate the adjusted odds ratio (aOR) of OLP in individuals who had received amalgam and composite resin restorations, root canal therapy, and tooth extraction over a follow-up duration of five years. RESULTS: There were no significantly different odds of OLP for those who underwent either amalgam (aOR = 0.948, 95% CI = 0.853-1.053, p = 0.3170) or resin restorations (aOR = 1.007, 95% CI = 0.978-1.037, p = 0.6557) in both anterior and posterior teeth in an observational period of five  years after restorations. Root canal therapy was associated with significantly lower odds of OLP, with each additional root canal therapy attenuating the risk of OLP at an aOR of 0.771 (95% CI = 0.680-0.874, p = 0.0001) for both anterior (aOR = 0.786, 95% CI = 0.626-0.986, p = 0.0372) and posterior teeth (aOR = 0.762, 95% CI = 0.650-0.893, p = 0.0008). Likewise, each tooth extraction reduced the risk of OLP, with an aOR of 0.846 (95% CI = 0.772-0.927, p = 0.0003), especially for anterior teeth (aOR = 0.733, 95% CI = 0.595-0.904, p = 0.0037). CONCLUSIONS: We reported no significant association between dental restorations and consequent OLP, and significantly lower odds of OLP following both root canal therapy and tooth extraction.

Clinical Performance of Direct Posterior Composite Restorations in Patients with Amelogenesis Imperfecta.

The objective of this study was to analyze and assess the clinical performance of direct composite restorations using a nanohybrid and a nanofill composite material for posterior teeth in patients with amelogenesis imperfecta (AI). This study involved 15 patients between the ages of 14 and 30 years suffering from amelogenesis imperfecta (AI). During the study, the patients received direct composite restorations using either the Clearfil Majesty ES-2 (Kuraray Medical Inc, Tokyo, Japan) and Clearfil Universal Bond (Kuraray) or Filtek Ultimate Universal Restorative (3M ESPE, St Paul, MN, USA) and Single Bond Universal Adhesive (3M ESPE). The evaluations of the restorations were conducted per the modified USPHS criteria at the time of baseline as well as during the first-, second-, third-, and fourth-year follow-up sessions. After four years, it was observed that the cumulative success rate of direct posterior restorations was 98.1% for Clearfil Majesty ES-2 and 92.2% for Filtek Ultimate. During the study one Clearfil Majesty ES-2 restoration and four Filtek Ultimate restorations failed. There was a significant difference between Clearfil Majesty ES-2 and Filtek Ultimate in the color match in posterior restorations after three and four years. The causes of failure included marginal discoloration and caries, as well as fracture of the restoration. Hence, it can be stated that the use of nanohybrid or nanofill composites in posterior direct restorations in patients with AI looks promising. The failure rate of Clearfil Majesty ES-2 was found to be lower than that of Filtek Ultimate restorations. Clinically, the rate of optimum restorations conducted for partial discoloration, marginal adaptation, color match, and surface texture were observed to be higher when Clearfil Majesty ES-2 was used. However, additional studies are needed to assess the clinical performance of direct posterior composite materials in patients with AI.

Do composite resin polishing systems damage enamel?

Finishing and polishing of composite resin restorations may cause damage to the bordering enamel. Although many studies have investigated the effect of polish on restorative materials, few have quantified the effect on bordering enamel. The objective of this study was to compare enamel loss surrounding composite restorations after finishing and polishing sequences. The null hypothesis was that there would be no difference in enamel loss between different finishing and polishing sequences. Class V preparations on the buccal and lingual surfaces of 15 extracted human molars were restored with a composite resin and assigned to 1 of 2 finishing and polishing sequences, so that each tooth underwent both sequences (n = 15 per sequence). In sequence 1, a tungsten carbide finishing bur and aluminum oxide polishing discs were used; in sequence 2, a diamond finishing bur, aluminum oxide-impregnated finishing cup, and diamond-impregnated polishing cup were used. Tooth surfaces were scanned with an optical scanner after preparation, finishing, initial polishing, and final polishing. The finishing and polishing scans were aligned to the preparation scan using Cumulus software. The depth of enamel surface loss was calculated and statistically analyzed (α = 0.05; paired t test). Most enamel loss (mean [SD]) resulted from the finishing step with the tungsten carbide bur (51.8 [21.3] µm) or diamond bur (43.3 [12.6] µm). Each polishing step increased mean enamel loss by only a few microns. There was no statistically significant difference between the 2 finishing and polishing sequences. The majority of enamel damage during finishing and polishing of composite resin restorations resulted from the finishing burs. Little enamel was removed by either of the tested composite resin polishing systems.

The safety and biocompatibility of direct aesthetic restorative materials.

Restorative dental materials are among the most important medical devices in terms of the numbers of patients who benefit and the technical sophistication of the products. Many though contain toxic or noxious substances, including potentially sensitising resin monomers, photoinitiators, acidic polymers and glass or ceramic filler particles. Despite this, dental materials are among the safest medical devices in use today, with very few reports of adverse reactions or injuries among both patients or the dental team. This paper considers the potential for adverse reactions to dental materials, current evidence for harm and finally examines the reasons why in real-world clinical use the likelihood of an adverse event is extremely low. Medical devices regulations, responsible manufacture and clinical vigilance all appear to play important roles in ensuring that dental materials do not cause or present a risk to patients. While this excellent in-practice safety record is welcome, there is now increasing interest in the 'macro' scale biocompatibility of dental materials and their packaging in the environment, subjects that have been relatively neglected until recently. It was concluded that this should be a priority for future research and development and support is needed from governments alongside the manufacturing industry and the profession.

Dental material allergies and oral soft tissue reactions.

Dental materials can cause reactions to the oral mucosa and present to the general dental practitioner. These are often referred to as 'allergies' but are frequently lichenoid reactions. Most of these are related to dental amalgam restorations and can be remedied by replacing the restoration with another suitable material. Other metals, including gold, palladium, nickel and chrome, have also been reported to trigger mucosal changes. Less commonly, issues arise from other restorative materials, including denture acrylics, composites and glass polyalkenoates. Reactions are also reported due to endodontic and sealing materials. It is unclear what role skin 'patch' testing has in managing dental material allergies. This article aims to give the practitioner a clearer picture of dental material allergy issues and how they should be approached in primary dental practice.

Additional information of bitewings to first time clinical examination of caries and restoration status in permanent dentition.

OBJECTIVES: Identifying additional information obtained by X-rays combined with clinical examination concerning primary caries, caries adjacent to restorations and quality of restorations. MATERIAL AND METHODS: A total of 240 adult patients, equally distributed in gender and six age-groups, were randomly selected from an original study population of 4,402 subjects (DANHES). Clinical and radiographical registrations on occlusal and approximal surfaces in posterior teeth were categorized into unrestored surfaces (sound/primary caries) and restored surfaces (without/with caries adjacent to restorations). Material and quality of restorations were also recorded. Chi-square and Fisher-exact tests were used for statistical analyses. RESULTS: Of potentially 11,520 surfaces, 3,015 occlusal and 5,112 approximal surfaces were analysed. Occlusal: Of 907 unrestored surfaces, 110 had primary caries and 53% were detected radiographically. A total of 183 of 2,108 restored surfaces had caries adjacent to restorations, and 99% were found radiographically. A total of 190 restorations were over/under-extended, and 89% were registered radiographically. Approximal: Of 2,649 unrestored surfaces 648 had primary caries, and 92% were registered radiographically. A total of 565 of 2,463 restored surfaces had caries adjacent to restorations, and 99% were found radiographically. A total of 638 restorations were over/under-extended, and 98% were found radiographically. For all restorations, material and depth influenced quality of restorations and incidence of caries adjacent to restorations. At least one independent variable (gender/age group/tooth-type/jaw/side/mesial-distal surface) influenced frequencies of primary caries, caries adjacent to restorations and quality of restorations. CONCLUSIONS: First-time clinical examination must be supplemented with X-rays to obtain a complete impression of caries status in posterior regions regarding diagnostics of caries, assessment of lesion depth and quality of restorations.

The effects of amalgam contamination and different surface modifications on microleakage of dentin bonded to bulk fill composite when using different adhesive protocols.

BACKGROUND: To evaluate the effect of amalgam contamination, different surface treatments, and adhesive protocols on dentin microleakage to bulk-fill composite resin material. METHODS: Forty teeth were fixed in (polyvinyl siloxane) PVS molds, and the Class II cavities were placed on mesial and distal aspects. Thirty teeth were restored by amalgam and thermocycled to 10,000 cycles (5 and 55 °C, 30-s dwell time). The rest were restored with Filtek one Bulk Fill composite without amalgam predecessor. Samples were divided into: G1 (dentin pretreated with 2% chlorhexidine gluconate), G2 (0.5 mm of dentin was removed), G3 (no surface modification), and G4 (control, where composite was bonded to sound dentin without amalgam predecessor.). Single Bond Universal Adhesive system was used to bond the composite material, by using the etch-and-rinse protocol in the mesial cavity preparation and self-etch protocol in the distal. Specimens underwent thermocycling for 5000 cycles, then embedded in silver nitrate and sectioned for stereomicroscope examination. Descriptive statistics, Mann-Whitney U test, and Kruskal-Wallis test were used to analyze the results at p < 0.05. RESULTS: The highest microleakage score values (4.00) were found in the G2, and G4 in etch-and-rinse protocol. While the lowest scores were found in G2 when using self-etching protocol (1.5). Lower microleakage values were associated with the chlorhexidine treatment group for both adhesive protocols. No significant differences were found between amalgam contaminated and non-contaminated groups. CONCLUSIONS: Amalgam contamination did not affect microleakage. Self-etching adhesive protocol significantly reduced microleakage for all groups irrespective of the surface treatment. Chlorhexidine pretreatment improved microleakage for both adhesive protocols but had no significant effect.

Analysis of dental amalgam fillings on primary Sjögren's syndrome: A population-based case-control study in Taiwan.

ABSTRACT: Primary Sjören's syndrome (pSS) is an autoimmune disease characterized by the inflammatory infiltrate and progressive dysfunction of salivary glands. Dental amalgam with mercury has been raised the public concerns regarding its purported mercury toxicity from dental amalgam to possible systemic inflammatory and immune reactions.In this study, a nationwide population-based database was employed to investigate the association of amalgam filling (AMF) and the risk of pSS. A retrospective case-control study was sourced from the Taiwanese National Health Insurance Research Database (NHIRD) from 2000 to 2013. Case and control groups were matched by sex, age, urbanization level, monthly income, and comorbidities using the propensity score method with a 1:1 ratio. In this study, 5848 cases and 5848 controls were included.The results demonstrated no statistically significant differences between AMF and pSS (odds ratio [OR]: 0.974, 95% confidence interval [CI] = 0.904-1.049). In addition, pSS was also not associated with AMF for women (OR: 0.743, 95% CI = 0.552-1.000) and men (OR: 1.006, 95% CI = 0.670-1.509), respectively.Taken together, evidence demonstrated that the association of AMF and pSS was inconsistent from this robust register databank.

Influence of Diode Laser for the Treatment of Dentin Hypersensitivity on Microleakage of Cervical Restorations.

Noncarious cervical lesions (NCCLs) are a common clinical finding often linked with dentin hypersensitivity (DH). Aim. The aim of the study was to evaluate the influence of diode laser for the treatment of DH on microleakage of subsequent NCCL restorations. Materials and Methods. Forty-eight extracted human premolars were collected. All teeth received standardized cervical preparation on both the buccal and palatal surfaces and were randomly divided into three groups (n = 16) according to the restorative material used: nanohybrid composite resin (CR), resin-modified glass ionomer (RMGI), and conventional glass ionomer (GIC). The prepared cavities on the palatal surfaces were treated by diode laser using SIROlaser Blue (Sirona Dental Systems, Bensheim, Germany) prior to restoration, while preparations on the buccal surfaces were directly restored. After thermocycling, the teeth were immersed in methylene blue dye for microleakage evaluation under 40x magnification at both occlusal and cervical margins. The Kruskal-Wallis test followed by the Bonferroni tests was conducted to determine inter- and intragroup differences (P < 0.05). Results. All restorative materials tested showed some degree of microleakage with no statistically significantly different scores with or without the use of laser desensitization prior to restorative treatment. Group CR showed the least microleakage, followed by group RMGI, while group GIC showed the highest. Cervical margins showed greater microleakage than the occlusal margins where the difference was statistically significant in the RMGI group without laser pretreatment (P = 0.006) and in both groups CR (P = 0.02) and RMGI (P = 0.006) with the laser pretreatment. Conclusion. Application of diode laser for the treatment of DH prior to the restoration of teeth with NCCL did not affect the microleakage of all the restorative materials tested. All the materials showed some degree of microleakage, which was higher in gingival margins compared to occlusal margins. The resin composite shows the least microleakage among all the tested materials.

Effect of 940 nm laser diode irradiation prior to bonding procedure on postoperative sensitivity following class II composite restorations: a split-mouth randomized clinical trial.

The aim of this study was to evaluate the effect of 940 nm laser diode on class II composite cavities prior to bonding and restoration process on the postoperative sensitivity (POS). Thirty patients with two bilateral premolars with mesio or disto-occlusal carious lesions were evaluated. In each patient, the teeth were randomly divided into the control and laser groups. After cavity preparation and isolation and before the bonding process, the laser group was subjected to 940 nm irradiation (Epic 10, Biolase, USA) by 400 µ tip continuously at 100 mW with 398 J/cm2 energy density of tip, which was applied for 5 s at a distance of 2 mm on the axial wall of the cavity. In the control group, irradiation was performed by using the aiming beam. Access cavity was then restored with a composite resin. Cold sensitivity was measured using a cold spray application on the middle third of teeth buccal surface at baseline (before the intervention), 1, 14, and 30 days after the restoration by visual analog scale (VAS) criteria. The mean Friedman and Wilcoxon signed-rank tests were used for data analysis. It was shown that in both laser and control groups, the VAS was significantly decreased at all times compared to the baseline (p ≤ 0.05). There was no statistically significant difference between the mean VAS of two groups at baseline and first day (p ≤ 0.05), but at 14 and 30 days after the intervention, it was significantly lower in the laser group (p ≤ 0.05). The results of this study demonstrated that the cavity pretreatment with laser diode (940 nm) effectively reduces the postoperative sensitivity in class II composite restorations.